Introduction to WLAN Topology and Composition Principles

Click the blue text above to follow us

Resource Release

Huawei Certified Beginner to Advanced Practical Course

↓ Scan to watch practical videos ↓

Introduction to WLAN Topology and Composition Principles

1. WLAN Composition Structure

The WLAN composition structure includes stations (STA), wireless medium (WM), access points (AP), and distributed systems (DS).

1. Station (STA)

Generally refers to terminal devices in the WLAN network, such as wireless network cards, wireless modules in mobile phones, etc. STA can be mobile or fixed. Each STA supports functions such as authentication, de-authentication, encryption, and data transmission. It is the most basic unit of WLAN.

2. Wireless Medium (WM)

The wireless medium is the transmission medium for communication between stations and access points in the WLAN. Here, it refers to the atmosphere, which is a good medium for the transmission of radio waves and infrared.

3. Access Point (AP)

Basic Functions:

① As an access point, it completes the access and communication connections between non-access point stations and the distributed system within the same BSS (Basic Service Set).

② Acts as a bridge between the wireless network and the distributed system, completing the bridging function between the two.

③ As the control center of the BSS, it manages and controls other non-access point stations.

4. Distributed System (DS)

The limitations of the physical layer coverage determine the direct communication distance between stations. To expand the coverage, multiple access points can be connected to enable communication between them. The logical component connecting multiple access points is called a distributed system.

2. Basic Service Set (BSS)

① The basic service set is the basic unit of the 802.11 wireless local area network, which can contain multiple STAs.

② The area covered by the BSS is called the basic service area (BSA), where STAs can communicate with each other.

③ If the signal strength received by the wireless interface is above the threshold, it ensures that STAs can move within the BSA without losing connection to the BSS. Signal strength (BSSI).

④ Each BSS has a Basic Service Set Identifier (BSSID), which is actually the MAC address of the AP’s wireless RF card (48 bits).

3. Service Set Identifier (SSID)

Identifies the logical name of 802.11, commonly referred to as the name of the wireless network. Users can configure it freely, and the SSID can consist of up to 32 characters, case-sensitive, configured in all APs and STAs’ wireless RF cards.

BSSID and SSID are not the same.

SSID Hidden:

Most APs have the function to hide SSID, which is a simple security measure.

Multiple SSIDs:

Early 802.11 chips could only create a single BSS, providing users with a single logical network. As the number of users increased, a single logical network could no longer meet the needs of users.

The multi-SSID technology can divide a wireless local area network into several subnetworks, each requiring independent authentication. Only users who pass the authentication can enter the corresponding subnetwork, preventing unauthorized users from entering this network. Meanwhile, the AP will assign different BSSIDs corresponding to these SSIDs.

Source: Internet, infringement deleted

Course consultation add: HCIE666CCIE

↑ Or scan the QR code above ↑

If you have any technical points or content you want to see

You can leave a message below to let us know!

Related posts

Leave a Comment Cancel reply